With the development of solid-state lighting technologies, light-emitting diodes (LEDs) have become the preferred solution in many lighting projects, as they are highly efficient, environmentally friendly, have long service lives, and save energy. Consequently, they are increasingly used in lighting products. Generally, an LED lamp comprises a light source and a driver circuit composed of an LED array. The driver circuit converts the power supply to a direct current that is required for the LED light source to emit light.
Today, fluorescent lamps are gradually being eliminated. To replace them, more and more users are using LED lamps. However, since fluorescent lamps are generally driven by a magnetic or electronic ballast, after the fluorescent lamp is removed from a lamp, the magnetic or electronic ballast is still present in the lamp. Consequently, an LED lamp cannot be mounted directly in a circuit that contains a magnetic or electronic ballast.
When an LED lamp is used to replace a fluorescent lamp that uses a magnetic ballast, that is, when the LED lamp is to be mounted in a circuit that contains a magnetic ballast, since the power of an LED light source is generally less than that of the original fluorescent lamp, if the LED lamp is mounted directly, the inductive current and capacitance current in the magnetic ballast do not match, and the system power factor is reduced. This results in an excessively large input current that exceeds the current limit of the magnetic ballast, thereby creating a safety hazard. Therefore, there is a need for an improved LED lamp and corresponding driver circuit that can solve at least one of the aforementioned problems.